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At least 631 records · Page 35

The POPOP4 library and codes for preparing secondary gamma-ray production cross sections

The POPOP4 code for converting secondary gamma ray yield data to multigroup secondary gamma ray production cross sections and the POPOP4 library of secondary gamma ray yield data are described. Recent results of the testing of uranium and iron data sets from the POPOP4 library are given. The data sets were tested by comparing calculated secondary gamma ray pulse height spectra measured at the ORNL TSR-II reactor.

Ford, W. E., III↗

Data collection and preparation of authoritative reviews on space food and nutrition research

The collection and classification of information for a manually operated information retrieval system on the subject of space food and nutrition research are described. The system as it currently exists is designed for retrieval of documents, either in hard copy or on microfiche, from the technical files of the MSC Food and Nutrition Section by accession number, author, and/or subject. The system could readily be extended to include retrieval by affiliation, report and contract number, and sponsoring agency should the need arise. It can also be easily converted to computerized retrieval. At present the information retrieval system contains nearly 3000 documents which consist of technical papers, contractors' reports, and reprints obtained from the food and nutrition files at MSC, Technical Library, the library at the Texas Medical Center in Houston, the BMI Technical Libraries, Dr. E. B. Truitt at MBI, and the OSU Medical Libraries. Additional work was done to compile 18 selected bibliographies on subjects of immediate interest on the MSC Food and Nutrition Section.

Source record↗

Remote sensing of soils, land forms, and land use in the northern Great Plains in preparation for ERTS applications

Research to determine the optimum time or season for obtaining imagery to identify and map soil limitations was conducted in the proposed Oahe irrigation project area in South Dakota. The optimum time for securing photographs or imagery is when the soil surface patterns are most apparent. For cultivated areas similar to the study area, May is the optimum time. The density slicing analysis of the May image provided additional and more accurate information than did the existing soil map. The soil boundaries were more accurately located. The use of a density analysis system for an operational soil survey has not been tested, but is obviously dependent upon securing excellent photographs for interpretation. The colors or densities of photographs will have to be corrected for sun angle effects, vignetting effects, and processing to have maximum effectiveness for mapping soil limitations. Rangeland sites were established in Bennett County, South Dakota to determine the usefulness of ERTS imagery. Imagery from these areas was interpreted for land use and drainage patterns.

Frazee, C. J.↗

Exploratory development and services for preparing and examining ultrathin polished sections of lunar rocks and particulates, part 1

Development of improved procedures is reported for three classes of lunar materials: dense rocks, breccias, and particulates. High quality ultrathin sections of these materials are obtained. Lists of equipment and supplies, procedures, photomicrographic documentation, and training are provided. Advantages of ultrathin polished sections for conventional and unconventional optical microscopy methods are described. Recommendations are provided for use of ultrathin sections in lunar rock studies, for further refinement of ultrathinning procedures, and for additional training efforts to establish a capability at the Manned Space Center. For Part 2, See N72-50754.

Beauchamp, R. H.↗

Remote sensing of soils, land forms, and land use in the northern great plains in preparation for ERTS applications

Research to determine the optimum time or season for obtaining imagery to identify and map soil limitations was conducted in the proposed Oahe irrigation project area in South Dakota. The optimum time for securing photographs or imagery is when the soil surface patterns are most apparent. For cultivated areas similar to the study area, May is the optimum time. The fields are cultivated or the planted crop has not yet masked soil surface features. Soil limitations in 59 percent of the field of the flight line could be mapped using the above criteria. The remaining fields cannot be mapped because the vegetation or growing crops do not express features related to soil differences. This suggests that imagery from more than one year is necessary to map completely the soil limitations of Oahe area by remote sensing techniques. Imagery from the other times studied is not suitable for identifying and mapping soil limitations of Oahe area by remote sensing techniques. Imagery from the other times studied is not suitable for identifying and mapping soil limitations because the vegetative cover masked the soil surface and does not reflect soil differences.

Frazee, C. J.↗

Detection of a lysosomal carboxypeptidase and a lysosomal dipeptidase in highly-purified dipeptidyl aminopeptidase I /cathepsin C/ and the elimination of their activities from preparations used to sequence peptides.

Description of the properties of a carboxypeptidase, termed 'catheptic carboxypeptidase C,' and a dipeptidase, termed 'Ser-Met dipeptidase.' Both were found in highly purified DAP I from either beef spleen or rat liver. Methods are described for the removal or selective inactivation of these contaminating enzymes.

Mcdonald, J. K.↗

Use of a CO2 laser to prepare chondrule-like spherules from supercooled molten oxide and silicate droplets.

Chondrule-like spherules were formed from individual freely falling subcooled droplets of alumina, enstatite, forsterite, enstatite-albite and forsterite-albite mixtures that had been melted with a focused continuous CO2 laser beam. Their textures (rimmed, excentro-radial, barred, glassy) are strikingly similar to those of many meteoritic chondrules. It is suggested that the phenomena associated with rapid crystallization from the supercooled melt are responsible for the various textures observed in the artificial spherules as well as in similar meteoritic chondrules. It is suggested that the textures observed would also result from rapid crystallization of relatively slowly cooling molten droplets that may have been produced in larger scale events, including condensation from a nebula of solar composition and solidification in an ambient medium of high temperature.

Nelson, L. S.↗

Analysis of large-scale Martian topography variations. I - Data preparation from earth-based radar, earth-based CO2 spectroscopy, and Mariners 6 and 7 CO2 spectroscopy.

Using direct radar ranging of surface heights on Mars and spectrophotometric observations of absorptions produced by carbon dioxide molecules in the Martian atmosphere, data have been obtained on Martian topographical variations at spatial resolutions ranging from about 100 to 1000 km. These data have been studied and analyzed. As a result, a surface height contour map has been produced which clearly reveals a structural complex of blocks and basins whose distribution enhances the magnitude of low-degree surface harmonics. It is emphasized that Mars possesses unexpectedly pronounced topography which can have important geophysical consequences.

Wells, R. A.↗

Preparation of prepreg graphite tape with insoluble polymer

Powdered polymer is finely ground. Second polymer, soluble, is mixed with appropriate solvent. Milled polymer and graphite filaments are added to soluble polymer-solvent solution to create slurry. Slurry is dried, and when ready for processing, the soluble, binder-polymer is removed by heat during precure or cure cycle.

Yates, C. I.↗

Preparative electrophoresis experiment design

A multifaceted study supporting the NASA programs to develop a space electrophoresis capability has been conducted. The study involved principally the technique of continuous free electrophoresis. It comprised a critical review of the art, study of new techniques for enhancing resolution and stability, and construction and initial testing of a high resolution cell. The effort resulted in a significant advance in free electrophoresis technique. It has provided also a much improved base for developments exploiting the added advantages of a zero-gravity environment.

Thiehler, A.↗